Method for recycling shale gas skid-mounted equipment

Abstract

The invention discloses a method for recycling shale gas skid-mounted equipment. The method comprises the following steps: S1, collecting data; s2, equipment classification: classifying old equipment one by one according to equipment types, use conditions, specifications and models and pressure vessel types, and establishing an identity information list; the equipment is classified by combining the value of the equipment, whether the equipment information is complete and the appearance detection result; s3, returning the equipment to a factory; s4, making a preliminary maintenance and transformation scheme; s5, dismounting the equipment; s6, cleaning and derusting; s7, equipment detection; s8, formulating a specific maintenance and transformation scheme; s9, equipment maintenance and transformation; s10, detecting after maintenance; s11, reassembling the equipment; s12, carrying out overall detection; s13, anti-corrosion paint spraying; s14, performing evaluation after multiplexing; according to the scheme, equipment is repeatedly utilized in combination with a new capacity construction plan, the construction period of a new project can be shortened, and the overall benefit of the project is improved.

Description

Technical Field

[0001] The invention relates to the technical field of shale gas skid-mounted equipment reuse, and in particular to a method for reusing shale gas skid-mounted equipment. Background Art

[0002] The development characteristics of shale gas mainly present "three lows, one high, one fast and one long", including low single well production, fast production decline but long economic life of single well. Shale gas is divided into four production stages according to pressure and production, namely, drainage period, relatively stable production period, decline period and low-pressure small production period. Shale gas well stations are equipped with gathering and transportation skids according to the designed production. As the production stage advances, the shale gas pressure, sand content, water content, etc. gradually decrease, and the skid processing capacity is surplus. Therefore, in the "China Petroleum Shale Gas Ground Construction Standardization Design Manual", the reuse of equipment ideas was formulated through modularization, skid standardization and other measures. In addition, the basic principles and qualified evaluation standards for reuse are proposed in the "Technical Regulations for Reusability Evaluation of Skid-Mounted Production Equipment on Shale Gas Platforms Q / SYXN0558".

[0003] With the deepening of shale gas development, a large number of idle gathering and transportation skid-mounted devices not only cause waste of production capacity, but also increase the unit maintenance cost. However, these devices still have high use value. Through reasonable repair and reuse, the purchase cost of new equipment can be significantly reduced, resource waste can be reduced, and it is helpful to achieve circular economy and sustainable development.

[0004] However, due to the lack of sufficient reuse methods in actual application, the reuse of equipment based solely on the experience and requirements of the skid-mounted manufacturer cannot guarantee the safety and effectiveness of the equipment after reuse. Summary of the invention

[0005] The purpose of the present invention is to provide a method for reusing shale gas skid-mounted equipment to address the above shortcomings, solving the problem of the lack of sufficient reuse methods in the prior art. However, if the reuse is carried out only based on the experience and requirements of the skid-mounted manufacturer, the safety and use effect of the equipment after reuse cannot be guaranteed.

[0006] The present invention is achieved through the following scheme:

[0007] The following steps are involved:

[0008] S1, Data collection: In the early stage of equipment reuse, it is necessary to collect basic data of each device according to the old equipment list submitted by the user unit;

[0009] S2, Equipment Classification: Classify the old equipment one by one according to the equipment type, working condition, specification model and pressure vessel category, and establish an identity information list; and classify the equipment according to the value of the equipment itself, whether the equipment information is complete, and the appearance inspection results;

[0010] S3, return the equipment to the factory; S4, formulate a preliminary maintenance and renovation plan; S5, dismantle the equipment; S6, clean and remove rust; S7, inspect the equipment; S8, formulate a specific maintenance and renovation plan; S9, repair and renovate the equipment; S10, inspect after maintenance; S11, reinstall the equipment; S12, overall inspection; S13, spray anti-corrosion paint; S14, evaluate after reuse.

[0011] In S1, the basic information includes:

[0012] (1) Design drawings, pressure vessel calculations, technical specifications, design operating conditions, and design service life;

[0013] (2) Manufacturing information and quality certification documents;

[0014] (3) Actual operating medium, operating pressure and temperature, actual content of corrosive substances, and medium changes;

[0015] (4) Documents on commissioning time, service time, inspection and maintenance records, intermediate modification records, and regular inspection records;

[0016] (5) Identity information, appearance inspection, specifications, models and weight of skid-mounted equipment, containers and major equipment.

[0017] In S2, the specific categories of classification are:

[0018] Category 1: large skid-mounted equipment, important skid-mounted equipment or skid-mounted equipment with special design and use conditions;

[0019] Category II: skid-mounted equipment with complete documentation, good appearance and short service life;

[0020] Category 3: Equipment with incomplete data files, equipment that has exceeded its design service life, or equipment whose materials have been eliminated by current standards.

[0021] Due to the importance or particularity of the first type of skid-mounted equipment, special maintenance plans are often formulated based on actual conditions for reuse; while the third type lacks information and cannot be scientifically evaluated and analyzed, making it unsuitable for reuse; in S3, specifically, based on the equipment classification, equipment that meets the second type of standards will be transported back to the manufacturing and processing workshop in the repair plant for repair.

[0022] In S4, specifically, a reused maintenance log is prepared based on the collected basic information of the equipment, the maintenance number is determined for each device, a single pipe diagram is drawn, the container, equipment, instrument, valve, pipeline and weld position numbers are compiled, and physical identification is done; for the same type of equipment, the parts of the pipeline that are severely damaged due to high medium flow rate and strong corrosion are listed as the sections that must be replaced to reduce unnecessary inspection workload.

[0023] In S6, specifically, the media inside the equipment and pipelines are removed, and the surface and inner wall of the container are washed with a high-pressure water gun and a rust removal device to remove attached dirt and expose the inner wall body to meet the conditions for endoscopic inspection.

[0024] In S7, the following aspects are specifically included;

[0025] (1) Instruments and safety valves are sent to a third party for inspection and calibration;

[0026] (2) Whether the product nameplate of the pressure vessel is clear, whether the body, interface parts, welding joints, etc. of the pressure vessel have cracks, overheating, deformation, leakage, mechanical contact damage, whether the outer surface is corroded, whether the sealing fasteners are intact, and whether the seal is intact;

[0027] (3) Check whether the dismantled valve has leakage, cracks, sand holes, corrosion, whether the valve stem is deformed or rusted, whether the nameplate is clear, whether the seal is intact, and whether the valve switch is flexible;

[0028] (4) Conduct a single water pressure test on the valves that meet the requirements for maximum operating pressure;

[0029] (5) Whether there is corrosion, cracks, leakage, bulging, deformation, mechanical damage, or arc burns on the outer surfaces of pipelines and pipe fittings;

[0030] (6) Conduct power-on test inside the skid to ensure that the electrical pathways, grounding equipment and junction box facilities are in good condition;

[0031] (7) Whether the skid seat, skid plate and steel structure parts are flat without warping and obvious deformation, whether there are serious corrosion and rust, and whether there are obvious defects in the welding parts;

[0032] (8) Perform endoscopic inspection on pressure vessels and pipelines, observe the damage to the inner wall, and mark and record abnormalities and suspected abnormalities;

[0033] (9) Use a thickness gauge to measure the thickness of pressure vessels and pipelines at fixed points, and mark any abnormal thickness measurement areas. The thickness measurement results are verified with the endoscope results;

[0034] (10) Perform 100% radiographic testing on pressure vessels and pipeline welds. If radiographic testing is not possible, use 100% ultrasonic testing instead.

[0035] In S8, specifically, according to the test results, the unqualified parts are checked for the severity of damage, and the strength of the damaged parts is checked if necessary, and repair or replacement is clearly stated in the plan. For locations with more serious damage, such as the pipes before separation after sewage discharge and throttling, which are subject to greater erosion and corrosion, they can be directly replaced based on usage experience.

[0036] In S10, specifically, (1) 100% X-ray and 100% ultrasonic testing is performed on the welds of the newly welded pipe;

[0037] (2) The new valve unit shall be used after passing the pressure test;

[0038] (3) New instruments and electrical equipment must be inspected and qualified before use.

[0039] 10. A method for recycling shale gas skid-mounted equipment as claimed in claim 9, characterized in that: in S12, specifically, (1) after the entire skid is repaired, the maintenance unit is responsible for carrying out pressure resistance test and tightness test on the pressure vessel, the pressure vessel is carried out in accordance with the requirements of the design documents, the pressure pipeline is pressure tested in sections according to the pressure grade, the specific operation and qualification standards are carried out in accordance with the original design pressure test conditions, and after the test, a test report is provided;

[0040] (2) Check the inlet and outlet dimensions, horizontality and verticality of the equipment, and conduct a team connection test for paired equipment;

[0041] (3) Skid-mounted power-on inspection. Pneumatic valves need to undergo signal and action tests, control valves need to undergo stroke action tests, and cut-off valves need to undergo switch action tests to ensure that instruments and automatic control valves are in good condition;

[0042] In S13, the whole skid is painted with anti-corrosion paint according to SY / T7036-2016 standard. Before anti-corrosion painting, the containers, pipelines, valves, actuators, instruments and meters are sandblasted and derusted according to actual needs. After anti-corrosion painting, the anti-corrosion layer is inspected and tested, including the following contents:

[0043] (1) Appearance inspection: All external surfaces should be flat and smooth, without defects such as damage, bubbling, cracking, peeling, etc.

[0044] (2) Thickness detection: Use a coating thickness gauge to measure the total dry film thickness of the anti-corrosion layer. Measure 5 locations for every 10 square meters of equipment. If the equipment is less than 10 square meters, measure 3 locations. The total dry film thickness of the anti-corrosion layer should comply with the corresponding provisions of the original coating plan.

[0045] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0046] 1. This plan combines the new capacity construction plan to reuse equipment, which can shorten the construction period of new projects and improve the overall benefits of the projects.

[0047] 2. This plan provides a method for classifying, evaluating and implementing old equipment. By formulating a series of maintenance methods and processes, the equipment can meet the evaluation standards, be ready for reuse and be reasonably economical.

[0048] 3. The new solution has a wide range of applications and is suitable for the reuse of most shale gas gathering and transportation skids.

[0049] 4. Strong operability and short maintenance cycle: This solution has been applied to the maintenance and renovation of hundreds of equipment. After practical application and optimization, the maintenance and renovation cycle of the new solution is about 20 days.

[0050] 5. The new solution is highly economical. After calculation, the maintenance and renovation costs are approximately 25% of the original equipment.

[0051] 6. Good reuse effect and strong safety. After actual application, this solution has been found that the original equipment has good adaptability under new working conditions and shows performance close to that of new equipment. Quality problems caused by incomplete maintenance rarely occur. DETAILED DESCRIPTION

[0052] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0053] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other equivalent or alternative features having similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0054] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "left", "right", etc. are directions or positional relationships, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a predetermined direction, be constructed and operated in a predetermined direction, and therefore cannot be understood as a limitation on the present invention.

[0055] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0056] Example 1

[0057] The present invention provides a technical solution:

[0058] A method for reusing shale gas skid-mounted equipment, which at least includes but is not limited to the following steps:

[0059] S1, Data Collection: In the early stage of equipment reuse, it is necessary to collect basic data of each device according to the old equipment list submitted by the user unit. The data needs to include:

[0060] (1) Original design data (design drawings, pressure vessel calculation sheet, technical specifications, design operating conditions, design service life, etc.);

[0061] (2) Manufacturing information and quality certification documents;

[0062] (3) Operation records (actual operating medium, operating pressure and temperature, actual content of corrosive substances, medium changes, etc.);

[0063] (4) Equipment archives (commissioning time, service time, inspection and maintenance records, intermediate modification records, and regular inspection records, etc.);

[0064] (5) On-site survey information (identity information, appearance inspection, specifications, models, weight, etc. of skid-mounted equipment, containers and other major equipment);

[0065] S2, Equipment Classification: Classify the old equipment one by one according to the equipment type, working condition, specification model and pressure vessel category, and establish an identity information list; and classify the equipment according to the value of the equipment itself, whether the equipment information is complete, and the appearance inspection results. The specific categories of classification are:

[0066] Category 1: large skid-mounted equipment, important skid-mounted equipment or skid-mounted equipment with special design and use conditions;

[0067] Category II: skid-mounted equipment with complete documentation, good appearance and short service life;

[0068] Category 3: Equipment with incomplete data files, equipment that has exceeded its design service life, or equipment whose materials have been eliminated by current standards.

[0069] The first type of skid-mounted equipment is important or special in itself, and special maintenance plans are often formulated according to actual conditions for reuse. However, the third type lacks data, and it is impossible to conduct scientific evaluation and analysis of the equipment itself, and it does not meet the conditions for reuse. Therefore, the patent of this invention is only applicable to the second type of skid-mounted equipment;

[0070] S3, equipment return: according to the equipment classification, the equipment that meets the Class II standard will be transported back to the manufacturing and processing workshop in the repair factory for repair;

[0071] S4, formulate a preliminary maintenance and renovation plan (draw a single pipe diagram and mark the pipe section valves);

[0072] Prepare a reuse maintenance record based on the collected basic equipment information, determine the maintenance number for each unit, draw a single pipe diagram, compile the position numbers of containers, equipment, instruments, valves, pipelines and welds, and do a good job of physical identification; for the same type of equipment, list the parts with high medium flow rate, strong corrosion or serious damage to the pipeline due to other factors as the pipe sections that must be replaced to reduce unnecessary inspection workload;

[0073] S5, equipment removal;

[0074] Disassemble containers, removable container components, equipment, instruments, valves and pipelines inside containers according to their numbers. Dismantled equipment and pipelines shall be placed in classified areas according to their identification.

[0075] S6, cleaning and rust removal;

[0076] Remove the media inside the equipment and pipelines, use high-pressure water guns and rust removal devices to rinse the surface and inner wall of the container, remove the attached dirt, expose the inner wall body, and meet the conditions for endoscopic inspection;

[0077] S7, equipment detection, specifically including the following aspects;

[0078] (1) Instruments and safety valves are sent to a third party for inspection and calibration;

[0079] (2) Whether the product nameplate of the pressure vessel is clear, whether the pressure vessel body, interface (valves, pipelines), welding joints, etc. have cracks, overheating, deformation, leakage, mechanical contact damage, whether the outer surface is corroded, whether the sealing fasteners are intact, and whether the seal is intact;

[0080] (3) Check whether the dismantled valve has leakage, cracks, sand holes, corrosion, whether the valve stem is deformed or rusted, whether the nameplate is clear, whether the seal is intact, and whether the valve switch is flexible;

[0081] (4) Conduct a single water pressure test on the valves that meet the requirements for maximum operating pressure;

[0082] (5) Whether there is corrosion, cracks, leakage, bulging, deformation, mechanical damage, arc burns, etc. on the outer surface of pipelines and pipe fittings;

[0083] (6) Conduct power-on test inside the skid to ensure that the electrical pathways, grounding equipment, junction boxes and other facilities are in good condition;

[0084] (7) Whether the skid seat, skid plate and other steel structure parts are flat without warping and obvious deformation, whether there are serious corrosion and rust, and whether there are obvious defects in the welding parts;

[0085] (8) Perform endoscopic inspection on pressure vessels and pipelines, observe the damage to the inner wall, and mark and record abnormalities and suspected abnormalities;

[0086] (9) Use a thickness gauge to measure the thickness of pressure vessels and pipelines at fixed points, and mark any abnormal thickness measurement areas. The thickness measurement results can be verified with the endoscope results;

[0087] (10) Conduct 100% radiographic testing on pressure vessels and pipeline welds. If radiographic testing conditions are unavailable, 100% ultrasonic testing may be used instead;

[0088] S8, formulate specific maintenance and renovation plans;

[0089] According to the test results, the unqualified parts are checked for the severity of damage and the strength of the damaged parts when necessary, and repair or replacement is clearly stated in the plan. For the more seriously damaged parts, such as the pipes before separation after sewage discharge and throttling, which are subject to greater erosion and corrosion, they can be directly replaced based on usage experience;

[0090] S9, equipment maintenance and renovation;

[0091] Repair and renovate the equipment according to the renovation plan.

[0092] S10, post-repair inspection;

[0093] (1) Conduct 100% radiographic and 100% ultrasonic testing on the welds of newly welded pipelines;

[0094] (2) The new valve unit shall be used after passing the pressure test;

[0095] (3) Newly replaced instruments and electrical equipment must be tested and qualified before use;

[0096] S11, equipment reinstallation;

[0097] After the repair and renovation, the equipment, pipelines, valves, instruments and meters are reinstalled according to the position numbers;

[0098] S12, overall inspection, includes the following aspects:

[0099] (1) After the whole skid is repaired, the maintenance unit is responsible for carrying out pressure resistance test and tightness test on the pressure vessel. The pressure vessel shall be tested in accordance with the requirements of the design documents, and the pressure pipeline shall be pressure tested in sections according to the pressure level. The specific operation and qualified standards shall be carried out in accordance with the original design pressure test conditions. After the test, a test report shall be provided;

[0100] (2) Check the inlet and outlet dimensions, horizontality and verticality of the equipment, and conduct a team connection test for paired equipment;

[0101] (3) Skid-mounted power-on inspection. Pneumatic valves need to undergo signal and action tests, control valves need to undergo stroke action tests, and cut-off valves need to undergo switch action tests to ensure that instruments and automatic control valves are in good condition;

[0102] S13, anti-corrosion spray paint;

[0103] The whole skid is painted with anti-corrosion paint (primer) according to SY / T7036-2016 standard; before anti-corrosion painting, the containers, pipelines, valves, actuators, instruments and meters are sandblasted and rusted according to actual needs. After anti-corrosion painting, the anti-corrosion layer should be inspected and tested, including the following contents:

[0104] (1) Appearance inspection: All external surfaces should be flat and smooth, without defects such as damage, bubbling, cracking, peeling, etc.

[0105] (2) Thickness detection: A coating thickness gauge should be used to measure the total dry film thickness of the anti-corrosion layer. Five locations should be randomly measured for every 10 square meters of equipment (every 80 meters of pipeline). When the equipment is less than 10 square meters (the pipeline is less than 80 meters), three locations should be randomly measured. The total dry film thickness of the anti-corrosion layer should comply with the corresponding provisions of the original coating plan.

[0106] S14, post-reuse evaluation;

[0107] After the repair is completed, according to the Technical Regulations for the Evaluation of Reusability of Skid-Mounted Production Equipment on Shale Gas Platforms

[0108] (Q / SYXN0558-2023) Chapter 5 Reusability Evaluation Related Requirements Carry out evaluation work, give evaluation conclusions and reuse suggestions, and issue an evaluation report.

[0109] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for reusing shale gas skid-mounted equipment, characterized in that: The following steps are involved: S1, Data collection: In the early stage of equipment reuse, it is necessary to collect basic data of each device according to the old equipment list submitted by the user unit; S2, Equipment Classification: Classify the old equipment one by one according to the equipment type, working condition, specification model and pressure vessel category, and establish an identity information list; and classify the equipment according to the value of the equipment itself, whether the equipment information is complete, and the appearance inspection results; S3, return the equipment to the factory; S4, formulate a preliminary maintenance and renovation plan; S5, equipment dismantling; S6, cleaning and rust removal; S7, equipment inspection; S8, formulation of specific maintenance and renovation plan; S9, equipment maintenance and renovation; S10, post-maintenance inspection; S11, equipment reinstallation; S12, overall inspection; S13, anti-corrosion painting; S14, evaluation after reuse.

2. A method for recycling shale gas skid-mounted equipment according to claim 1, characterized in that: In S1, the basic information includes: (1) Design drawings, pressure vessel calculations, technical specifications, design operating conditions, and design service life; (2) Manufacturing information and quality certification documents; (3) Actual operating medium, operating pressure and temperature, actual content of corrosive substances, and medium changes; (4) Documents on commissioning time, service time, inspection and maintenance records, intermediate modification records, and regular inspection records; (5) Identity information, appearance inspection, specifications, models and weight of skid-mounted equipment, containers and major equipment.

3. A method for recycling shale gas skid-mounted equipment according to claim 2, characterized in that: In S2, the specific categories of classification are: Category 1: large skid-mounted equipment, important skid-mounted equipment or skid-mounted equipment with special design and use conditions; Category II: skid-mounted equipment with complete documentation, good appearance and short service life; Category III: Equipment with incomplete data files, equipment that has exceeded its design service life or whose materials have been eliminated by current standards; The first type of skid-mounted equipment is important or special in itself, so when it is reused, a special maintenance plan is often formulated based on the actual situation. However, the third type lacks data and cannot be scientifically evaluated and analyzed, so it does not meet the conditions for reuse. In S3, specifically, according to the equipment classification, the equipment that meets the second-class standard is transported back to the manufacturing and processing workshop in the repair factory for repair.

4. A method for recycling shale gas skid-mounted equipment according to claim 3, characterized in that: In S4, specifically, a reused maintenance log is prepared based on the collected basic information of the equipment, the maintenance number is determined for each device, a single pipe diagram is drawn, the container, equipment, instrument, valve, pipeline and weld position numbers are compiled, and physical identification is done; for the same type of equipment, the parts of the pipeline that are severely damaged due to high medium flow rate and strong corrosion are listed as the sections that must be replaced to reduce unnecessary inspection workload.

5. A method for recycling shale gas skid-mounted equipment according to claim 4, characterized in that: In S6, specifically, the media inside the equipment and pipelines are removed, and the surface and inner wall of the container are washed with a high-pressure water gun and a rust removal device to remove attached dirt and expose the inner wall body to meet the conditions for endoscopic inspection.

6. A method for recycling shale gas skid-mounted equipment according to any one of claims 1 to 5, characterized in that: In S7, the following aspects are specifically included; (1) Instruments and safety valves are sent to a third party for inspection and calibration; (2) Whether the product nameplate of the pressure vessel is clear, whether the body, interface parts and welded joints of the pressure vessel have cracks, overheating, deformation, leakage, mechanical contact damage, whether the outer surface is corroded, whether the sealing fasteners are intact, and whether the seal is intact; (3) Check whether the dismantled valve has leakage, cracks, sand holes, corrosion, whether the valve stem is deformed or rusted, whether the nameplate is clear, whether the seal is intact, and whether the valve switch is flexible; (4) Conduct a single water pressure test on the valves that meet the requirements for maximum operating pressure; (5) Whether the outer surface of the pipeline or pipe fittings is corroded, cracked, leaking, bulging, deformed, mechanically damaged, or burned by electric arc; (6) Conduct power-on test inside the skid to ensure that the electrical pathways, grounding equipment and junction box facilities are in good condition; (7) Whether the skid seat, skid plate and steel structure parts are flat without warping and obvious deformation, whether there are serious corrosion and rust, and whether there are obvious defects in the welding parts; (8) Perform endoscopic inspection on pressure vessels and pipelines, observe the damage to the inner wall, and mark and record abnormalities and suspected abnormalities; (9) Use a thickness gauge to measure the thickness of pressure vessels and pipelines at fixed points, and mark the abnormal thickness measurement areas; the thickness measurement results are verified with the endoscope results; (10) Conduct 100% radiographic testing on pressure vessel and pipeline welds. If radiographic testing is not possible, use 100% ultrasonic testing instead.

7. A method for recycling shale gas skid-mounted equipment according to claim 6, characterized in that: In S7, specifically, based on the test results, the strength of the damaged parts is checked if necessary depending on the severity of the damage of the unqualified parts. The pipes before separation after sewage discharge and throttling are directly replaced based on usage experience because they are severely eroded and corroded.

8. The method for recycling shale gas skid-mounted equipment according to claim 7, characterized in that: In S10, specifically, (1) 100% X-ray and 100% ultrasonic testing is performed on the welds of the newly welded pipe; (2) The new valve unit shall be used after passing the pressure test; (3) New instruments and electrical equipment must be inspected and qualified before use.

9. A method for recycling shale gas skid-mounted equipment according to claim 8, characterized in that: In S12, specifically, (1) after the entire skid is repaired, the maintenance unit is responsible for conducting pressure tests and tightness tests on the pressure vessel. The pressure vessel is tested in accordance with the requirements of the design documents, and the pressure pipeline is tested separately according to the pressure level. The specific operation and qualification standards are carried out in accordance with the original design pressure test conditions. After the test, a test report is provided; (2) Check the inlet and outlet dimensions, horizontality and verticality of the equipment, and conduct a team connection test for paired equipment; (3) Check the skid-mounted equipment by powering on it. Pneumatic valves need to undergo signal and action tests, regulating valves need to undergo stroke action tests, and cut-off valves need to undergo switch action tests to ensure that instruments and automatic control valves are in good condition.

10. The method for recycling shale gas skid-mounted equipment according to claim 8, characterized in that: In S13, the whole skid is painted with anti-corrosion paint according to SY / T7036-2016 standard. Before anti-corrosion painting, the containers, pipelines, valves, actuators, instruments and meters are sandblasted and rust-removed according to actual needs. After anti-corrosion painting, the anti-corrosion layer is inspected and tested, including the following contents: (1) Appearance inspection: All external surfaces should be flat and smooth, without any defects such as damage, blistering, cracking or peeling; (2) Thickness detection: Use a coating thickness gauge to measure the total dry film thickness of the anti-corrosion layer. Measure 5 locations for every 10 square meters of equipment. If the equipment is less than 10 square meters, measure 3 locations. The total dry film thickness of the anti-corrosion layer should comply with the corresponding provisions of the original coating plan.